Projects / Programmes source: ARIS

Causes and effect of December 2017 wind throw on further development of European beech and Silver fir stands in Slovenian Forests

Research activity

Code Science Field Subfield
4.01.01  Biotechnical sciences  Forestry, wood and paper technology  Forest - forestry 

Code Science Field
B430  Biomedical sciences  Sylviculture, forestry, forestry technology 

Code Science Field
4.01  Agricultural and Veterinary Sciences  Agriculture, Forestry and Fisheries 
natural disturbances, wind throw, restoration, regeneration, development perspective, European beech and fir forests
Evaluation (rules)
source: COBISS
Researchers (14)
no. Code Name and surname Research area Role Period No. of publicationsNo. of publications
1.  52922  Ajša Alagić  Forestry, wood and paper technology  Researcher  2020 - 2021  62 
2.  15493  PhD Matjaž Čater  Forestry, wood and paper technology  Head  2018 - 2021  299 
3.  11253  PhD Jurij Diaci  Forestry, wood and paper technology  Researcher  2018 - 2021  716 
4.  29164  PhD Mitja Ferlan  Forestry, wood and paper technology  Researcher  2018 - 2021  222 
5.  34320  PhD Gal Fidej  Forestry, wood and paper technology  Researcher  2018 - 2021  86 
6.  39600  PhD Jernej Jevšenak  Forestry, wood and paper technology  Researcher  2018 - 2021  105 
7.  16067  PhD Andrej Kobler  Forestry, wood and paper technology  Researcher  2018 - 2021  289 
8.  17333  Robert Krajnc    Technical associate  2018 - 2021  56 
9.  11595  PhD Tomislav Levanič  Forestry, wood and paper technology  Researcher  2018 - 2021  614 
10.  20842  PhD Aleksander Marinšek  Forestry, wood and paper technology  Researcher  2018 - 2021  386 
11.  27544  PhD Thomas Andrew Nagel  Biotechnical sciences  Researcher  2018 - 2021  234 
12.  24368  PhD Andrej Rozman  Forestry, wood and paper technology  Researcher  2020 - 2021  113 
13.  21043  PhD Dušan Roženbergar  Forestry, wood and paper technology  Researcher  2018 - 2021  231 
14.  28401  PhD Peter Železnik  Forestry, wood and paper technology  Researcher  2018 - 2021  188 
Organisations (2)
no. Code Research organisation City Registration number No. of publicationsNo. of publications
1.  0404  Slovenian Forestry Institute  Ljubljana  5051673000  11,988 
2.  0481  University of Ljubljana, Biotechnical Faculty  Ljubljana  1626914  66,215 
In the December 2017 natural disaster, 211,000 ha of forests were severely damaged by 2.201,000 m3; according to the share of forested area, the damage was greatest in Forest management district (FMD) Kočevje (69%), FMD Nazarje (38%), FMD Sl. Gradec (33%), FMD Postojna (22%) and FMD Ljubljana (19%). Mostly affected were the beech silver fir stands. Depending on the occurrence, the pace of occurrence and its consequences raise several question of the key factors that influence the formation of such disasters: soil properties (depth, soil characteristics), stand parameters (diameter, dimensional ratio, structure of fallen trees) or even possible internal wood anomalies/ defects (ring shakes, wet heart), which influence the increased exposure and vulnerability of stands in the case of wind disasters. Diameter and quality structure of fallen trees is also questionable. Wind disasters affect large areas of different development stages. In some places, left trees within protected areas may be used for cultivation measures. Disasters adversely affect the yield of owners especially when the share of economically interesting tree species is small and their regeneration is compromised, while low density does not allow the return of high quality assortments. Natural regeneration on areas affected by winds is often accompanied by regeneration with planting, which can significantly shorten the period required to form a closed canopy with a target mixture of economically interesting tree species. Planting often requires protection and care, which are expensive and can create problems for the future resistance of forest stands. In countries with predominant sustainable silvicultural systems, the current debate on the appropriateness of natural restoration or restoration with planting remains opened. In Slovenia are knowledge, skills and general capacity for artificial regeneration in decline. From the field there are frequent reports of low survival rate of seedlings, which may relate to various factors: from poor quality of plants and planting, to the lack of maintenance and protection of seedlings against browsing. In systems based on natural regeneration, herbivores reduce stocks of seeds and the density and speed of juvenile growth. It is assumed that herbivorous wildlife in the events of natural disasters increases their living stock because of increased food supply. By eating, peeling and rubbing younger trees, they slow down natural regeneration and quality and cause an unwanted change in the target species composition. Based on the defined goals, 6 work packages (WP’s) have been designed to answer the key issues related to the natural disaster from 2017. In the affected areas, we target objects will be defined, where we will: 1. Determine the physical soil properties of areas that were affected by wind damage and control areas (without damage) in in relation to weather and microsite conditions (rootstock, exposition, altitude, species structure of stands, microrelief) and define the characteristics of root systems of the most affected tree species - fir, spruce and beech (WP1); 2. Model of potential threat to the broader range of fir-beech forests will be established considering the possibility of extreme weather events on similar forest sites. The data will be provided by WP 1 and weather data from micrometeorological stations (GIS) and ARSO; 3. on the same objects affected by winds, we will compare the effectiveness and efficiency of natural and artificial regeneration with planting and determine the key site factors for the successful regeneration of the affected areas. The methodology of monitoring the success of the development of natural regeneration and restoration with planting will complement the methods of protecting the young stands against browsing using chemical and electronic deterrents. The data will be complemented by the inventory lists and the ecophysiological response measurements (WP 3); 4. The efficiency of the r
Significance for science
Due to environmental changes have become natural disasters more and more frequent in recent decades. Affected forest areas may endanger the implementation of forest ecosystem services - protection against erosion, water management, water and air cleaning, carbon sinks and timber supply. Research shows an increasing share of beech admixture and severe decline in fir during the last 100 years; successful preservation and regeneration of fir is therefore a crucial part of applied measures in forests adaptation to climate change. The expert public will be presented with assessments of current situation and development trends regarding the restoration of forests affected by extreme winds in Slovenia and abroad. In such a way, critical points in today's system of planning and carrying out work on forest restoration will be identified, which will indirectly enable the preparation of measures to improve the situation in this area. A number of trainees from the Slovenian Forest Service, doctoral candidate, several graduates and postdoctoral students will be involved in the project work.  In such way the project represents also an important contribution to the development of young forestry personnel.
Significance for the country
Project results will provide development of strategies and political decisions which will benefit the restoration of forested areas affected by natural disasters (in particular extreme wind), especially by regeneration.Within action strategies decision-making about natural or artificial regeneration and protection of the young forest would be emphasized. In such way ecosystem services will be provided and reduction of long-term economic losses for forest owners will be reduced. At the same time the forests will achieve their final value much faster. An important part of the project proposal represents assesment of the economic / assortment structure, since it establishes a solid basis for further comparisons of the management / cultivation methods and the direct economic value of a particular forest stand. Depending on the assortment quality and potential amount of damage in forest stands, it would be possible to evaluate required measures to reduce risks and ensure optimal economic efficiency at an ever-increasing occurrence of extreme weather events.
Most important scientific results Annual report 2019, 2020
Most important socioeconomically and culturally relevant results Annual report 2018, 2019, 2020
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